The purpose of this study is to investigate whether the addition of oral maintenance chemotherapy with O-TIE (Etoposide, Idarubicin, Trofosfamide) for 6 months improves the event free survival (EFS) in patients with localised high-risk RMS and RMS-like Soft Tissue Sarcoma.

Inclusion Criteria:

• written informed consent for registration, randomisation, data collection/transfer, and tumour material asservation available

• pathologically (including molecular pathology) proven diagnosis of rhabdomyosarcoma (RMS) or RMS-like soft tissue sarcoma (STS) and tumour material available for pathology review

• Rhabdomyosarcoma of the "High Risk" Group, i.e.:

  • RME, N0, M0, IRS II&III, >5 cm or >10 years in EXT, HN-PM, OTH, UG-BP
  • RME, N1, M0, any IRS-group, any size or age
  • RMA, NO, M0, any IRS-group, any size or age (exception: paratesticular RMA are not eligible) or

• Rhabdomyosarcoma of the "Very High Risk" Group, i.e.:

  • RMA, N1, MO, IRS II&III, any size or age or
  • localised high-risk RMS-like Soft Tissue Sarcoma, i.e.:
  • EES, pPNET, UDS: any N, M0, any IRS-group, any size or age
  • SySa, any N, M0, any size or age (exception: SySa IRSI&II, not T2b, N0, M0 are not eligible)

• no pre-existing illness preventing treatment (esp. those listed in the medicinal product information, e.g. cardiac, hepatic, metabolic, or renal dysfunction; hypersensitivity)

• no previous malignant tumours

• available for long term follow up through the treating centre

• in remission (according to the CWS-2007-HR definition (see X7.1.8X)) at the time of randomisation after standard multimodal therapy e.g. according to the CWS-guidance

Exclusion Criteria:

• pregnant or lactating women
• other medical condition precluding treatment with protocol therapy (e.g. HIV, psychiatric disorder, etc.)
• for sexually active females and males in Arm B (O-TIE treatment): refusal to use effective contraception (e.g. oral, IUD)